Strawberry plant called `Camarosa`

ABSTRACT

`Camarosa` is a short-day (June bearing) cultivar similar to `Chandler` (U.S. Plant Pat. No. 5,262) but with greater total productivity, substantially greater early productivitiy, larger fruit, firmer fruit, and is a more vigorous plant.

DESCRIPTION

This invention relates to a new and distinctive short-day type cultivar designated as `Camarosa`, which resulted from a cross performed in 1988 between the cultivar `Douglas` (U.S. Plant Pat. No. 4,487) and advanced selection Cal 85.218-605.

`Camarosa` was first fruited at the University of California South Coast Research and Extension Center, near Irvine, Calif. in 1989, where it was selected, originally designated Cal 88.24-603, and propagated asexually by runners. Asexual propagules from this original source have been tested at the South Coast Research and Extension Center, the Watsonville Strawberry Research Facility, and to a limited extent in grower fields starting in 1990.

In the Drawings:

FIG. 1 shows the general flowering and fruiting characteristics of the plant;

FIG. 2 shows a typical mature leaf during late spring; and

FIG. 3 shows representative mid-season fruit.

`Camarosa` is typical of short-day types and produces fruit over an extended period when treated appropriately in arid, subtropical climates. `Camarosa` has a substantially greater yield than `Douglas` and greater fruit firmness. The production pattern for `Camarosa` is similar to that for `Chandler` (U.S. Plant Pat. No. 5,262), although it produces substantially greater quantities of early-season fruit. `Camarosa` will be of special interest for winter plantings, where `Chandler` has been successful, and in summer plantings where `Pajaro` (U.S. Plant Pat. No. 4,538) has been successful.

Plants and Foliage

Fruiting plants of `Camarosa` are larger, more erect, and more vigorous than plants of `Chandler`, and are generally similar in form to plants of `Oso Grande` (U.S. Plant Pat. No. 6,578). `Camarosa` forms branch crowns in greater quantity than `Chandler` with similar branching to `Oso Grande`. When propagated in the nursery, `Camarosa` has similar or greater runner production capacity compared with `Chandler`. Comparative statistics for foliar characters, including leaf color, near mid-season are given for the three cultivars in Table 1, with visual comparisons of leaf color to the Munsell color scale (Nickerson Color Fan) given in Table 5. Leaf color is distinctly lighter on the underside for `Camarosa`; the differential is similar to that for `Chandler` and not as large as for `Oso Grande`. Individual leaflets for `Camarosa` are larger, somewhat longer and more narrow than for `Chandler`, and are less rounded than for `Oso Grande`. Leaves (including petioles) are similar in length to `Chandler`, but are much broader. Petioles are thicker and more stiff than those of `Chandler` and are similar to those of `Oso Grande`. Paired stipules, borne in a median position on the petiole, appear as small, stalked, ovate to heart-shaped structures on some leaves for `Camarosa` and on most leaves for the comparison cultivars. Stipule size varies greatly both within and among individual plants for `Camarosa`, and one or both stipules are frequently absent or may abscise as the leaf matures. Leaf and petiole pubescence characters for `Camarosa` are similar to those for `Oso Grande`, except that tomentum on leaves are less dense. Also, leaves for `Camarosa` are similar in reflectance to `Chandler` but darker green (less yellow), and similar in color intensity to `Oso Grande`. Visual comparisons of fruit color according to the Munsell color scale (Nickerson Color Fan) are given in Table 5. `Camarosa` has concave leaves; less concave than leaves of `Chandler`, and similar to those of `Oso Grande` .

Isozymes in Leaf Extracts

`Camarosa` has been classified for three isozyme systems using starch gel electrophoresis (Table 2): Phosophoglucoisomerase (PGI), Leucine Aminopeptidase (LAP), and Phosphoglucomutase (PGM). It is distinguishable from all other short-day cultivars released to date. For electrophoretic procedures see: J. Amer. Soc. Hort. Sci. 106:684-687.

Disease and Pest Reaction

`Camarosa` is moderately susceptible to common leaf spot (Ramularia tulasnei) and relatively resistant to powdery mildew (Sphaerotheca macularis). When treated properly, it has equal or greater tolerance to two-spotted spidermites (Tetranychus urticae) than `Chandler`. `Camarosa` is tolerant to strawberry viruses encountered in California.

                  TABLE 1                                                          ______________________________________                                         Foliar characteristics for                                                     `Camarosa`, `Chandler`, and `Oso Grande`.                                                Cultivar                                                             Foliar Character                                                                           `Camarosa` `Chandler` `Oso Grande`                                 ______________________________________                                         Mid-tier leaflet                                                               Length (mm)                                                                    mean        97.4       82.4       77.2                                         range       80-117     78-94      75-80                                        Width (mm)                                                                     mean        79.8       71.4       67.6                                         range       70-92      63-88      62-71                                        Mid-tier leaf                                                                  Length (mm)                                                                    mean        234.2      244.2      191.6                                        range       210-253    218-262    170-200                                      Width (mm)                                                                     mean        143.6      148.0      137.2                                        range       135-180    132-158    130-149                                      Leaf color                                                                     (CIELAB)*                                                                      L*                                                                             mean        31.5       31.4       31.9                                         range       28.4-34.5  27.1-33.3  29.9-33.0                                    a*                                                                             mean        -5.9       -8.0       -5.3                                         range       -3.1--9.4  -5.2--8.2  -4.2--8.3                                    b*                                                                             mean        14.0       16.0       15.5                                         range       11.1-20.7  12.9-21.4  12.5-20.6                                    # leaflets/leaf                                                                            3          3          3                                            Leaf convexity                                                                             concave    concave    concave                                      Serrations                                                                     number      few        many       moderate                                     shape       semi-round semi-pointed                                                                              semi-round                                   Leaf pubescence                                                                            moderate   moderate/  moderate/                                                           sparse     heavy                                        Petiole pubescence                                                             density     heavy      heavy      heavy                                        direction   perpendicular                                                                             acropetal  perpendicular                                ______________________________________                                          *CIELAB is the abbreviation of the international color system known as         "Commission Internationale De L'Eclairage" 1978. Recommendations on            uniform color spaces - color difference equations, psychometric color          terms, Supplement No. 2 to CIE Publication No. 15. PARIS.                

                  TABLE 2                                                          ______________________________________                                         Isozyme phenotypes for                                                         `Camarosa`, `Chandler`, and `Oso Grande`.                                      Cultivar                                                                       Locus   `Camarosa`   `Chandler`                                                                               `Oso Grande`                                    ______________________________________                                         PGI     A2           A1        A2                                              LAP     B3           B3        B3                                              PGM     C1           C1        C2                                              ______________________________________                                    

Flowering, Fruiting, Fruit, and Production Characteristics

Comparative statistics for flower and fruit characters, including fruit color, near mid-season are given for the three cultivars in Table 3. The primary flowers for `Camarosa` are similar in size to `Chandler` and `Oso Grande`, whereas the sepals are somewhat larger than for the comparison cultivars. The calyx for `Camarosa` varies from slightly indented to slightly necked, and each primary flower has 5-6 petals. The fruit shape for `Camarosa` can vary but is typically a very flat conic, and is easily distinguished from `Chandler` (flat conic, with some long conic) and `Oso Grande` (rounded or blocky conic). External fruit color for `Camarosa` is similar to `Chandler` and `Oso Grande,` and the fruit is at least as glossy as `Chandler`; internal color is darker than for `Chandler` and substantially darker than for `Oso Grande`. Achenes vary from light red to dark red, and are even with the fruit surface or slightly indented.

`Camarosa` has been tested under a variety of cultural regimes, and optimal performance is obtained when nursery treatments, preplant chilling regimes, plant densities, and nutritional programs similar to those that optimize performance for `Chandler` are used. In general, `Camarosa` is more adapted to early-season planting with less supplemental chilling than `Chandler`.

When treated with appropriate planting regimes, `Camarosa` has larger fruit and produces greater yields than `Chandler` (Table 4); `Camarosa` has greater yield but smaller fruit than `Oso Grande`. `Camarosa` is similar to `Chandler` and `Oso Grande` in its production pattern, although it produces substantially more early-season fruit than either comparison cultivar (with conventional winter planting). Commercial appearance ratings have been comparable to or better than those for `Chandler`. Fruit for `Camarosa` is substantially firmer than fruit from `Chandler`; `Camarosa` is about as firm as `Oso Grande`. Subjectively, `Camarosa` has very good flavor, somewhat less aromatic than `Chandler`, but with better acid balance and more aromatic components than `Oso Grande`. The fruit will be outstanding for both fresh market and processing, due to its firm flesh and very dark internal color, and will be useful for home garden purposes.

                  TABLE 3                                                          ______________________________________                                         Flower and fruit characters for                                                `Camarosa`, `Chandler`, and `Oso Grande`.                                                  Cultivar                                                           Character     `Camarosa`                                                                               `Chandler`                                                                               `Oso Grande`                                 ______________________________________                                         # petals                                                                       mean           6.3       6.6       5.0                                         range         5-7       6-8       5-5                                          Flower position                                                                              even/     even/     exposed                                      (relative to foliage)                                                                        exposed   exposed                                                Calyx diam. (mm)                                                               mean          57.1      47.7      34.1                                         range         50-63     45-53     27-38                                        Corolla diam. (mm)                                                             mean          39.3      39.3      32.2                                         range         35-42     36-46     27-41                                        Fruit shape                                                                    length/width   1.13      1.33      1.06                                        ratio                                                                          subjective    flat/     flat conic                                                                               blocky/conic                                               some conic                                                       Calyx position                                                                               even/slight                                                                              even/slight                                                                              even/slight                                                indent    neck      indent                                       Seed position even/slight                                                                              even/slight                                                                              even                                                       indent    indent                                                 Fruit color (CIELAB)                                                           external                                                                       L*            23.1      23.6      22.4                                         a*            29.7      38.5      31.2                                         b*            16.6      14.8      17.2                                         internal                                                                       L*            43.6      46.2      54.1                                         a*            40.8      39.1      30.4                                         b*            30.9      29.4      22.7                                         ______________________________________                                    

                  TABLE 4                                                          ______________________________________                                         Performance for selection `Camarosa` compared with `Oso                        Grande` and `Chandler` at the South Coast Research and                         Extension Center in 1991. All plants were dug from the South                   Coast nursery on October 1 and planted October 2 (68"/4-row                    beds, 23,061 plants/A, 100 g/plant = 425 Crates/A).                                   Yield  Total             Appear-                                               To 4/1 Yield    Size     ance   Firm-                                          (g/plant)                                                                             (g/plant)                                                                               (g/fruit)                                                                               Score  ness                                    ______________________________________                                         `Camarosa`                                                                              555      2,380    24.6   4.4    4.7                                   `Chandler`                                                                              463      1,738    23.3   3.9    4.0                                   `Oso Grande`                                                                            530      1,675    25.0   3.8    4.9                                   ______________________________________                                    

                  TABLE 5                                                          ______________________________________                                         Munsell color classification for leaf and fruit characters.                    Munsell Leaf Color Classes                                                                           Munsell Fruit                                            Upper          Lower      Color Classes                                        Item    (Adaxial)  (Abaxial)  External                                                                               Internal                                 ______________________________________                                         Chandler                                                                               5GY 4/3    5GY 5/6    5R 5/13 7R 5/13                                          5GY 5/6               5R 4/12                                          Oso     5GY 4/3    5GY 5/6    5R 5/13 7.5R 7/9                                         5GY 3/2    7.5GY 6/8  7.5R 5/13                                                                              7.5R 6/12                                Camarosa                                                                               5GY 4/3    5GY 5/6    7.5R 4/11                                                                              7.5R 5/13                                                              7.5R 3/6                                                                               7.5R 4/11                                ______________________________________                                     

We claim:
 1. The new and distinct variety of strawberry plant illustrated and described and having the characteristics above enumerated. 